Prerequisites
This page states some of the assumed knowledge for readers of the NOC wiki. Creating a new page for each background concept would excessively increase the number of pages in the wiki. Instead, background concepts can be grouped on pages for the courses in which those concepts would usually be taught. Use UNSW courses as a guide as to which concepts should be grouped together. Network technologies e.g. courses that use textbooks by Tanenbaum & Wetherall, Kurose & Ross, or Peterson & Davie, e.g. UNSW TELE3118 Protocols are listed in the layer that they usually control, rather than the layer in which they operate. eg. DHCP and routing protocols control network layer IP addresses and paths, so are listed as part of the network layer, even if they are usually implemented as application layer protocols that operate over a transport protocol such as TCP or UDP. Topics that span layers Network layering: Physical Layer, Link Layer, Network Layer, Transport Layer, Application Layer, OSI Reference Model protocol, PDU, packet, frame , segment, fragmentation and reassembly demultiplexing identifiers, Ethertype, IP protocol, port number, PDU, segmentation and reassembly, header decoding octet An octet is a unit of digital information in computing and telecommunications that consists of eight bits. The term is often used when the term byte might be ambigous, as there is no standard for the size of the byte Standards? e.g. backwards compatibility Network standards organisations: IEEE 802, IETF Requests For Comments (RFCs), OSI, ITU : IETF: The Internet Eginneering Task Force (IETF) develops and promotes Internet standards, cooperating closely with the W3C and ISO/IEC standards bodies and dealing in particular with standards of the Internet protocol suite. It is an open standards organization, with no formal membership or membership requirements.1 : Network devices: host, interface - IP, interface - network interface card?, links, routers, switches, hub, server topology of a network Equipment manufacturers: Cisco, HP, Huawei Addressing, e.g. Link-Local addresses, MAC addresses, IP addresses, unicast, broadcast, multicast error control coding / Hamming distance / ARQ / retransmission / acknowledgements Physical layer cables - UTP Physics: impedance mismatch, change of refractive index codeword Link layer Medium Access Control (MAC) MAC protocols: Ethernet, Token ring; Ethernet: frame length requirements, preamble, SFD, CRC bridges/switches Spanning Tree Protocol packet capture / promiscuous mode Local network monitoring (sniffing) As opposed to Remote Network Monitoring e.g. by using Wiresharkor packet capture libraries Further reading In Wikipedia: Packet capture Packet analyzer Wireshark VLAN Address Resolution Protocol ARP ARP Network layer ICMP Internet Protocol, IPv4, IPv6, TTL IPX duplicate IP addresses Link-local Address A link-local address is an Internet Protocol address that is intended only for communications within the segment of a local network (a link) or a point-to-point connection that a host is connected to. Routers do not forward packets with link-local addresses. routing protocols, Link-State routing, Distance-Vector routing source routing EGP ping traceroute Dynamic Host Configuration Protocol (DHCP) Autonomous System Transport layer TCP, UDP Australian network management, TCP also refers to Telecommunications Consumer Protection for which a code of conduct was [http://www.acma.gov.au/WEB/STANDARD/pc=PC_311151 issued in 2008 and revised before being issued in 2012 ] DCCP, SCTP, TLS Sockets programming API htons() Application layer Domain Name System (DNS) HTTP, SMTP, worm, RPC web browser Network security e.g. UNSW TELE3119 Not assumed, but would enhance understanding of some aspects of this course Transport Layer Security cryptography / encryption key - cryptographic Denial Of Service (DOS) attacks Computing Hexadecimal booting, coldStart, warmStart durable and volatile memory 2s-complement arithmetic NULL termination of strings e.g. data types, e.g. signed and unsigned integers, enumerated types interrupts vs polling mutual exclusion - concurrency - threads etc - atomic operations Mathematics Matrix manipulation Engineering hysteresis reliability: MTTF etc Unsorted Ethernet UDP IP Address , Subnet Mask , RFC Routing metrics definition Link-state routing, distance-vector routing Address Resolution Protocol(ARP) is a telecommunications protocol used for resolution of network layer addresses into link layer addresses, a critical function in multiple-access networks. Address Resolution Protocol (ARP) exists solely to glue together the IP and Ethernet networking layers. Since networking hardware such as switches, hubs, and bridges operate on Ethernet frames, they are unaware of the higher layer data carried by these frames . Similarly, IP layer devices, operating on IP packets need to be able to transmit their IP data on Ethernets. ARP defines the conversation by which IP capable hosts can exchange mappings of their Ethernet and IP addressing. 1-http://en.wikipedia.org/wiki/Address_Resolution_Protocol2-http://linux-ip.net/html/ether-arp.html Category:All